Element identity
Atomic number, symbol, relative atomic mass display and periodic position are established reference data.
Atomic / electronic model
Ground-state electron configuration and atomic reference values are compiled/evaluated data; orbital graphics are teaching probability models, not photographs.
Material / molecular structure
The displayed ordinary structure is based on established material or molecular science; simplified viewers are labelled as teaching schematics where exact crystallographic coordinates are not rendered.
Temperature / phase path
Transition values are reference/evaluated values for the stated teaching path; pressure, purity and allotropy can matter.
Geography
Real pins use reviewed place/dataset context. Conceptual layers are used when country pins would imply false occurrence, unsafe inventory or an incomplete global distribution.
The lens describes evidence status, not confidence theatre. “Unknown” is kept unknown, and teaching schematics are not presented as direct measurements.
Xenon (Xe)
Xenon is element 54, a heavy noble gas that overturned the old idea that noble gases are completely inert. Its closed 5p shell coexists with a real chemistry of xenon fluorides and oxides under suitable conditions.
Xenon atomic number, mass, electron configuration and key properties
Xenon: quick answers
How many protons, neutrons and electrons does xenon have?
Xenon’s atomic number is 54, so every xenon atom has 54 protons, and a neutral atom also has 54 electrons. Its most common natural isotope, xenon-132, has 78 neutrons (other isotopes have different neutron counts).
What is the symbol for xenon?
The chemical symbol for xenon is Xe.
Is xenon a solid, liquid or gas at room temperature?
Xenon is a gas at room temperature (about 25 °C).
What family (group) is xenon in?
Xenon is a noble gas, in group 18, period 5 of the periodic table.
How many valence electrons does xenon have?
Xenon has 8 valence electrons, the electrons in its outer shell, which matches its position in group 18.
What is the electron configuration of xenon?
The ground-state electron configuration of xenon is [Kr] 4d¹⁰ 5s² 5p⁶.
From atomic number to chemistry
Read these as a chain of causes, not as isolated facts. Each step links to the concept hub if you want the underlying idea explained.
Fifty-four protons define xenon.
A closed outer shell explains low ordinary reactivity.
Xenon is the heavy noble gas below krypton.
Several xenon isotopes are important in spectroscopy, nuclear science and detectors.
Xenon’s normal liquid interval is narrow.
Xenon in its period and family
Xenon is in Group 18, Period 5 below krypton. Its closed 5p⁶ shell explains low ordinary reactivity, but xenon’s large, polarizable electron cloud allows chemistry with very strong oxidizing/fluorinating partners.
Xenon Visual Lab
Decode xenon’s tile, rotate a ¹³²Xe teaching nucleus and monatomic gas model, inspect 5s/5p probability clouds, explore its narrow cryogenic liquid interval, and connect noble-gas chemistry to lamps, medical anesthesia, spectroscopy and ion propulsion.
Every mark points to one exact feature
The numbered markers explain the same information system used throughout Element Lookup. Unknown or predicted fields remain visibly labelled rather than being replaced with guesses.
Xenon in one minute
Atomic number 54 means every xenon nucleus contains 54 protons.
Neutral xenon has the closed-shell configuration [Kr] 4d¹⁰ 5s² 5p⁶.
Xenon is a monatomic gas at ordinary conditions.
Xenon forms real compounds, including fluorides, despite being a noble gas.
Xenon’s normal liquid interval is narrow: melting near 161.4 K and boiling near 165.05 K.
Shell rings organize electron counts. They are not electron trajectories or orbital shapes.
2 · 8 · 18 · 18 · 8 electrons
The 5s model is spherical and the 5p model has the directional p angular form. These are isolated-atom probability models, not molecular orbitals of XeF₂ or XeF₄.
At ordinary conditions xenon is a monatomic noble gas. Cryogenic solid xenon forms a close-packed/FCC structure, but the ordinary-state viewer emphasizes separated Xe atoms.. The viewer is evidence-aware: measured structures are identified as such; unknown bulk structures stay unknown.
Teaching visualization; not a literal finite sample or thermal trajectory.What this model does—and does not—show
The 5s model is spherical and the 5p model has the directional p angular form. These are isolated-atom probability models, not molecular orbitals of XeF₂ or XeF₄.
Where do I meet xenon?
Clickable learning cards connect the element to materials, environment, technology, biology or research - depending on what the evidence actually supports.
High-intensity lighting
Xenon discharge lamps can produce intense broad-spectrum light used in specialized optical and projection applications.
A noble gas that really does make compounds
Xenon is the best counterexample to the classroom shortcut “noble gases never react.”
Closed-shell noble gas
Neutral xenon has a filled 5p6 outer shell and very low ordinary reactivity.
Krypton, xenon and radon
Polarizability grows down the noble-gas group, making xenon chemistry possible and heavy-element behavior increasingly complex.
| Outer shell | 4s² 4p⁶ |
|---|---|
| Context | noble gas |
| Outer shell | 5s² 5p⁶ |
|---|---|
| Compounds | XeF₂, XeF₄ and more |
| Boil | 165.05 K |
| Outer shell | 6s² 6p⁶ |
|---|---|
| Nuclear | radioactive |
Xenon properties: atomic, physical, thermal and chemical
Categories follow the science of this element rather than a fixed decorative template. Each row carries condition/provenance context and an evidence label; unknown values stay unknown.
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Atomic number | 54 | Source-reviewed; see Sources below | Evaluated |
| Relative atomic mass | 131.293 | Source-reviewed; see Sources below | Evaluated |
| Ground-state electron configuration | [Kr] 4d¹⁰ 5s² 5p⁶ | Source-reviewed; see Sources below | Evaluated |
| Group / period / block | Group 18 · Period 5 · p-block | Periodic-table placement | Evaluated |
| Electronegativity | 2.6 · commonly quoted Pauling value | Source-reviewed; see Sources below | Evaluated |
| Reference isotope | ¹³²Xe | Source-reviewed; see Sources below | Evaluated |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| State context | Colorless monatomic gas at 20 °C | Source-reviewed; see Sources below | Evaluated |
| Density | 0.005366 g/cm³ · gas reference | Source-reviewed; see Sources below | Evaluated |
| Material / molecular structure | Monatomic xenon gas · ordinary-state model | At ordinary conditions xenon is a monatomic noble gas. Cryogenic solid xenon forms a close-packed/FCC structure, but the ordinary-state viewer emphasizes separated Xe atoms. | Measured |
| Classification | Noble gas | Periodic-table / chemistry classification | Evaluated |
| Structure-model scope | At ordinary conditions xenon is a monatomic noble gas. Cryogenic solid xenon forms a close-packed/FCC structure, but the ordinary-state viewer emphasizes separated Xe atoms. | Teaching visualization; exact crystallographic coordinates are not implied unless stated. | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Melting / transition reference | 161.4 K | Source-reviewed; see Sources below | Evaluated |
| Boiling / gas reference | 165.051 K | Source-reviewed; see Sources below | Evaluated |
| Phase-path context | At approximately standard pressure, xenon is solid below about 161.4 K, liquid through a narrow interval to about 165.051 K, and gaseous above the boiling point. | Shared phase registry drives the slider, regions and markers. | Evaluated |
| Condition warning | Temperature and pressure define phase behavior; purity/allotropy may matter. | Teaching condition statement | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Common oxidation states | 0 ordinary · +2, +4, +6 and +8 occur in compounds | Source-reviewed; see Sources below | Evaluated |
| Ion / common ion context | No common stable monatomic ion | Source-reviewed; see Sources below | Evaluated |
| Periodic chemistry context | Xenon is in Group 18, Period 5 below krypton. Its closed 5p⁶ shell explains low ordinary reactivity, but xenon’s large, polarizable electron cloud allows chemistry with very strong oxidizing/fluorinating partners. | Element-specific interpretation | Reviewed |
| Chemistry caution | Elemental form, ions and compounds are distinct chemical objects. | Interpretive teaching rule | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| ¹³²Xe | Stable · one of the most abundant natural isotopes | Teaching nucleus contains 54 protons and 78 neutrons. | Evaluated |
| ¹²⁹Xe | Stable · major natural isotope | Important in spectroscopy and isotope studies. | Evaluated |
| ¹³¹Xe | Stable · major natural isotope | Another abundant natural isotope with nuclear-spin applications. | Evaluated |
| Xenon isotope family | Nine naturally occurring isotopes | Natural xenon has a rich isotope mixture, including stable and extremely long-lived species. | Evaluated |
| Teaching nucleus | ¹³²Xe · 54 protons + 78 neutrons | Reference isotope used in the nucleus model | Reviewed |
| Property | Value | Context / provenance | Evidence |
|---|---|---|---|
| Page evidence note | Atomic and phase values are measured/evaluated. The ordinary-state viewer uses separated atoms; low-temperature solid xenon is not shown as the room-temperature state. Noble-gas chemistry statements refer to known compounds, not to ordinary spontaneous reactivity. | Evidence summary for this guide | Reviewed |
| Structure evidence | At ordinary conditions xenon is a monatomic noble gas. Cryogenic solid xenon forms a close-packed/FCC structure, but the ordinary-state viewer emphasizes separated Xe atoms. | Measured structure, labelled schematic, prediction or explicit unknown as applicable. | Reviewed |
| Map evidence rule | Real pins are reviewed examples; conceptual layers are used when pins would mislead. | Geography Explorer 2.0 | Reviewed |
| Source set | 3 primary/reference links listed below | Open the Sources section for the actual references. | Reviewed |
Is Xenon a solid, liquid or gas? State at temperature
At approximately standard pressure, xenon is solid below about 161.4 K, liquid through a narrow interval to about 165.051 K, and gaseous above the boiling point.
Where on Earth is Xenon found or produced?
Who discovered Xenon, and when?
William Ramsay and Morris Travers discovered xenon while fractionating liquefied air.
Neil Bartlett prepared the first xenon compound, overturning the belief that noble gases could not form compounds.
Xenon became important in lamps, detectors, medicine and electric spacecraft propulsion.
Xenon chemistry and xenon-based detectors remain active examples of heavy-atom and noble-gas science.
From air to xenon products: a high-level path
Xenon is present only at trace levels in air, so it is recovered as a minor product of large-scale air separation.
Cryogenic separation concentrates rare gases before further purification; detailed plant operations are outside this guide.
Purified xenon is filled into controlled gas systems or further processed for specialized chemical/scientific uses.
Because xenon is scarce and expensive, some high-value applications recover and recycle the gas.
What is xenon used for?
Ion propulsion
Xenon is a common propellant for electric ion thrusters in satellites and deep-space missions.
Discharge lamps
Excited xenon emits intense light in specialized flash and arc lamps.
Medical anesthesia
Xenon can act as an anesthetic in specialized systems, though cost and supply constrain use.
Particle detectors
Liquid xenon provides a dense, clean detection medium in advanced physics experiments.
Xenon isotopes and natural abundance
¹³²Xe
Stable · one of the most abundant natural isotopesTeaching nucleus contains 54 protons and 78 neutrons.
¹²⁹Xe
Stable · major natural isotopeImportant in spectroscopy and isotope studies.
¹³¹Xe
Stable · major natural isotopeAnother abundant natural isotope with nuclear-spin applications.
Xenon isotope family
Nine naturally occurring isotopesNatural xenon has a rich isotope mixture, including stable and extremely long-lived species.
Five-question Xenon check
What is xenon’s atomic number?
What is xenon’s ordinary elemental form?
Can xenon form compounds?
What is xenon’s electron configuration?
Which use is associated with xenon?
Xenon questions students commonly ask
Each answer starts with the direct fact, then explains the chemistry, evidence or material context so the result is understandable rather than merely memorized.
What is xenon’s atomic number?
Short answer: 54.
Atomic number is defined by proton count, so 54 protons are what make an atom xenon. A neutral xenon atom also has 54 electrons, while isotopes can have different neutron counts without changing the element.
Key point: Atomic number = proton count.
Is xenon a noble gas?
Short answer: Yes. Xenon is a Group 18 noble gas with a closed 5p⁶ outer shell.
This guide classifies Xenon as a noble gas. Its periodic position is Period 5, p-block, Group 18. Xenon is in Group 18, Period 5 below krypton. Its closed 5p⁶ shell explains low ordinary reactivity, but xenon’s large, polarizable electron cloud allows chemistry with very strong oxidizing/fluorinating partners.
Key point: Periodic-table classification describes recurring atomic/chemical behavior; it does not make every element in a column physically identical.
What is xenon used for?
Short answer: Uses include ion propulsion, discharge lamps, specialized anesthesia and particle detectors.
Ion propulsion: Xenon is a common propellant for electric ion thrusters in satellites and deep-space missions. Discharge lamps: Excited xenon emits intense light in specialized flash and arc lamps. Xenon is a noble gas, not a 'nonreactive under every condition' gas. XeF₂, XeF₄ and other compounds are a powerful lesson that periodic trends are tendencies rather than absolute slogans.
Key point: Always distinguish the pure element from the compound, alloy, isotope or device material that actually performs the application.
Can xenon form compounds?
Short answer: Yes. Xenon fluorides and oxides are established compounds, so noble gases are not absolutely chemically inert.
Xenon is a noble gas, not a 'nonreactive under every condition' gas. XeF₂, XeF₄ and other compounds are a powerful lesson that periodic trends are tendencies rather than absolute slogans. Ion propulsion Xenon is a common propellant for electric ion thrusters in satellites and deep-space missions.
Key point: The pure element, its ions, compounds and alloys are different materials and should not be treated as interchangeable.
Who discovered xenon?
Short answer: William Ramsay and Morris Travers discovered xenon in London in 1898.
In 1898, William Ramsay and Morris Travers discovered xenon while fractionating liquefied air. In 1962, Neil Bartlett prepared the first xenon compound, overturning the belief that noble gases could not form compounds.
Key point: Discovery credit follows the historical evidence and accepted attribution, not just the earliest claim.
What is xenon’s electron configuration?
Short answer: [Kr] 4d¹⁰ 5s² 5p⁶.
The neutral-atom ground-state reference used on this page is [Kr] 4d¹⁰ 5s² 5p⁶. This is an isolated-atom reference: bonding and ion formation can change which outer electrons are present or chemically active. The listed common oxidation-state context is 0 ordinary · +2, +4, +6 and +8 occur in compounds, which helps connect the atomic configuration to ordinary chemistry without treating electron counting as a single universal rule.
Key point: Electron configuration is a ground-state atomic reference, not a literal picture of every compound.
How many valence electrons does xenon have?
Short answer: Eight in its outer shell: 5s² 5p⁶. That closed shell explains its low ordinary reactivity, although xenon can form compounds under suitable conditions.
The neutral-atom ground-state reference used on this page is [Kr] 4d¹⁰ 5s² 5p⁶. This is an isolated-atom reference: bonding and ion formation can change which outer electrons are present or chemically active. The listed common oxidation-state context is 0 ordinary · +2, +4, +6 and +8 occur in compounds, which helps connect the atomic configuration to ordinary chemistry without treating electron counting as a single universal rule.
Key point: Electron configuration is a ground-state atomic reference, not a literal picture of every compound.
Scientific sources for Xenon
- Royal Society of Chemistry - Xenon
- NIST - Atomic Data for Xenon
- NASA - Ion propulsion educational resources
Questions to ask next about Xenon
A good element lesson should lead to the next useful question, not end after a list of facts.
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